Cibcuit-intebbupting device



H. D. EVANS.

' CIRCUIT INTERRUPTING DEVICE.

APPLICATION FILED SEPT-16, 1918.

1 3 1 4,58 1 Patented Sept. 2, 1919.

WITNESSES INVENTOR M I Faber/"H2 Evans.

50 V vacuum-electric apparatus 5, such as a mer- UNITED STATES PATENT OFFICE.

ROBERT D. EVANS, F WIIiKI NSBUBG, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC & MANUIEIACTURING COMPANY, .A. CORPORATION OF PENNSYLVANId.

cmcurr-mrmmurrme DEVICE.

and State of Pennsylvania, have invented a new and useful Improvement in J Circuit- Interrupting Devices, of which the following is a specification.

My invention relates to clrcuit lnterrupting devices and particularly to vacuumelectric apparatus for interrupting directcurrent circuits.

One object of my invention is to provide an automatic circuit. interrupter having no movable parts. A further object of my inventionus to provide a device, of the above-indicated character, that shall be simple and 1nexpen-' sive'to construct and effective in its operation.

I vacuum-electric apparatus, such as a mer cury vapor valve or converter, and a transformer having two opposing windings of relation to the valve andthe winding having the less number ofturnsm When a short circuit or other disturbance occurs on the system to which the device is connected the quick change in current incident thereto causes current to be shunted through the condenser to the winding having the larger number of turns. This causes the current through the other winding to be still further reduced by reason of the opposing actions of the windings, and, since the valve is connected in series with the winding having the less number of turns, its arc will be extinguished to thereby interrupt the circuit. The single figure of the accompanying drawing is a diagrammatic view of an electric circuit embodying my invention.

*A direct-currentcircuit 1 comprises, in

general, a generator 2 or other source of electromotive force, an interrupting device 3 and a load 4.

Tl16 interrupting device 3 comprises a 'cury-vapor valve or converter, a transformer 6 having a primary winding 7 that is con- In practising my invention I provide a Specification of Letters Patent. Patented Sept, 2, 1919, Application filed September 16, 1918. Serial No. 254,219.

nected in series with the valve 5 on one side tkereof and a-winding 8 that is connected i series'with the valve 5 on the other side thereof. The winding 8 has a larger num-' ber of turns than the winding 7 and is so connected that it opposes the flow of the current through the winding 7. A condenser 9 is connected in shunt relation to that portion of the circuit 1 comprising the winding 7 and the valve 5.

When a short circuit or ground occurs on the circuit '1 the current traversing the cir-' cuit will quickly change'to cause current to be shunted through the condenser 9 around the winding 7 and the valve 5. Thus, the current that is shunted around the valve 5 and thecurrent traversing the valve will traverse the winding 8 which will induce a counter electromotive force in the winding 7 to thereby reduce the current traversing the same and the valve 5. If this currentis reduced to a predetermined relatively low value the arc of the valve 5 will be extinguished and since, under normal conditions, the direct current from the source 2 of electromotive force will not traverse the condenser 9, no current will be supplied to the load 4 after the arc is extinguished.

My invention is not limited to the specific apparatus illustrated as it may be variously modified without departing from the spirit and scope-of the invention as set forth in the appended claims. I I claimas my invention? 1. In a direct-current circuit, the combination with a vapor valve therein, of a transformer, a condenser, and'means for So connecting the windings of the transformer in series with the valve and the condenserin shunt to the valve and one winding of the transformer that, when the current traversing the circuit changes quickly, sufiicient current will be shunted from the valve to extinguish its arc. I

2. 1h an electric circuit, the combination with a vapor valve, of a transformer the windings of which are connected'in series with the valve, and a condenser connected in shunt relation to one of the windings and the 'valve, said windings being so connected that one opposes the other.

3., In an electric circuit, the combination with a vapor valve, of a transformer the windings ofwhich areconnected in series with the valve, and a condenser connected in shunt relation to one of the windings and i the valve, said winding being adapted to reduce the current through the valve when the condenser discharges.

4. In ane1ectr1c clrcult, the combination with a vapor valve, of'a transformer having two opposing windings connected in series with the valve, and means connected in shunt-relation to the valve for providing a bypass for, current around they valve and through 'voueofthe windings when the current traversing the circuit changes quickly.

5. In a 'direct-current circuit, the, combination with' a vacuum-electricapparatus, of a transformer having two opposing windings connected in series with the ap-n paratus on opposite sides thereof, and 'means for shunting current from one winding and the said apparatus under predetermined conditions. i

'- 6, In adir'ect-current circuit, the com bination with a vacuum-electric apparatus, of a transformer having two opposing windings connected in series with-the said-apparatus on opposite sides thereof, and a con denser for shunting current from one winding and the said apparatus under predetermined conditions.

bination with a vacuum-electric apparatus,

- of a transformer having two opposlng wind- 7. In a direct-current'circuit, the com-' difi'erent numbers of turns connected in series-with the valve, and a condenser conneeted in shunt relation to the valve and the winding having' the smaller number of turns forfthe purpose ofinc'reasing the current through'the other winding under predetermined conditions.

In testimony whereof, I have hereunto suloscribed my name this 4th day of Sept, 1918. K

Q ROBERT D. EVA-NS; 

